Bulletin 340] 



CONTROL OF THE POCKET GOPHER 



339 



WHEN TO TEAP AND POISON 

 Obviously, the time to combat gophers most successfully is he fore 

 the young make their appearance in the spring. Poisoning is very 

 effective, but hard to carry on in the dry season, especially during 

 August, September, and October, when it is most effective, since the 

 supply of green food is then scarcest. Trapping and poisoning are 

 most easily carried on soon after the green vegetation starts in the 

 early winter or spring, for the gophers are then most active. The wise 

 old males which usually cause the trapper most trouble seem to lose 

 their instinctive caution during the mating season, take poisoned bait 

 readily, and often blunder blindly into traps which they would never 

 enter at other times. Every female caught at this time, before the 

 young are born, means the destruction of from four to twelve gophers 

 for the current season. 



METHODS OF DESTEUCTION 



The five most effective methods of destroying gophers are: (1) 

 poisoning with strychnine ; (2) trapping; (3) flooding; (4) fumigation 

 with carbon bisulphide; (5) for permanent relief, the encouragement 

 and protection of the gopher's natural enemies, especially the barn owl 

 and the gopher snake. 



The solution of the gopher problem lies in a combination of two 

 or more of the above methods, rather than in any one of them (see 

 fig. 5). Where a large acreage is to be treated, poisoning with strych- 

 nine will be found most effective in reducing the pest. Traps are safe, 

 can be used at any time, and are effective in the hands of a man who 

 is not afraid to dig and who uses care in setting and in placing them. 

 Trapping is especially adapted to pastures, where there might 

 be danger of poisoning stock, and to gardens, orchards, and the banks 

 of irrigation ditches. Carbon bisulphide should be used only when 

 the ground is wet. Both traps and carbon bisulphide are good "follow- 

 up" methods in getting the gophers which refuse to take poisoned 

 bait. Land that can be successfully flooded, so as to drown out the 

 gophers, has usually been graded for irrigated crops such as alfalfa. 

 Flooding (irrigation) is therefore automatic, and it is comparatively 

 easy to hunt and kill gophers which are being flooded out. A man 

 that kills all gopher snakes and barn owls on his place will have to 

 fight gophers, and deservedly so. 



